In order to produce formation fluids from an earthen formation, wellbores can be drilled into the earthen formation to a desired depth for producing the formation fluids. During and/or after drilling a wellbore, various antennas can be deployed into the wellbore in a drill string assembly and/or a wireline logging tool to measure various wellbore parameters (e.g. formation resistivity, formation permeability, ranging distance and direction, tubing string integrity, cement sheath integrity, etc.). Loop antennas can be used as transmitters to inject energy (e.g. electrical, electromechanical, magnetic flux, etc.) into an earthen formation surrounding a wellbore. Loop antennas can also be used as receivers to receive energy from the earthen formation. Both the transmission and reception of energy by the antennas can be directly impacted by the antennas antenna design. Traditionally, loop antennas are formed of a standard wire conductor encased in a comparatively thick layer of thermoplastic or thermoset insulation and disposed within metal tubing shaped into a loop that encircles a tool body. The metal tubing provides rigidity to the insulated wire conductor and protects it from the downhole environment. Because the tubing is metal, in order for a signal to be transmitted or received from the wire without interference from the metal tubing, a gap or junction is formed in the metal tubing, which junction is covered by a dielectric material through which a signal can pass. One drawback to such an arrangement is that the metal tubing inhibits not only the strength of an electromagnetic signal, but also the direction the signal can travel.
Therefore, it will be readily appreciated that improvements in the arts of retaining ferrite beads to shield and/or direct signals to/from antennas are continually needed.